Question

For the geometric sequence with a1=4 and r=5 find a5

Answer 1

that is the geometric sequence

Answer 2

i dont know it

Answer 3

an = a1 * r ^ n-1
r = 5
a1 = 5
n = 5

a5 = 5 * 5^(5 - 1)
a5 = 5 * 5^4
a5 = 5 * 625
a5 = 3125

Fifth term is 3125

Answer 4

wait....I messed up

Answer 5

let me do it again....

Answer 6

okay. i got 31250

Answer 7

an = a1 * r ^ n - 1
a1 = 4
r = 5
n = 5
a5 = 4 * 5^(5 - 1)
a5 = 4 * 5^4
a5 = 4 * 625
a5 = 2500
How did you get 31250 ?

Answer 8

i found it in my notes from when i did this problem before

Answer 9

prob wrong

Answer 10

did you get n = 5 ? It has to be 5, for the 5th term. A1 = 4, r = 5. I can't see anything I did wrong.You weren't looking for the sum were you ?

Answer 11

let me check it this way...
a1 = 4
a2 = 4 x 5 = 20
a3 = 20 x 5 = 100
a4 = 100 x 5 = 500
a5 = 500 x 5 = 2500
correct........it is 2500

Answer 12

no not the sum

Answer 13

a5 = 2500